1 /* 2 * f_rndis.c -- RNDIS link function driver 3 * 4 * Copyright (C) 2003-2005,2008 David Brownell 5 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger 6 * Copyright (C) 2008 Nokia Corporation 7 * Copyright (C) 2009 Samsung Electronics 8 * Author: Michal Nazarewicz (mina86@mina86.com) 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 */ 15 16 /* #define VERBOSE_DEBUG */ 17 18 #include <linux/slab.h> 19 #include <linux/kernel.h> 20 #include <linux/module.h> 21 #include <linux/device.h> 22 #include <linux/etherdevice.h> 23 24 #include <linux/atomic.h> 25 26 #include "u_ether.h" 27 #include "u_ether_configfs.h" 28 #include "u_rndis.h" 29 #include "rndis.h" 30 #include "configfs.h" 31 32 /* 33 * This function is an RNDIS Ethernet port -- a Microsoft protocol that's 34 * been promoted instead of the standard CDC Ethernet. The published RNDIS 35 * spec is ambiguous, incomplete, and needlessly complex. Variants such as 36 * ActiveSync have even worse status in terms of specification. 37 * 38 * In short: it's a protocol controlled by (and for) Microsoft, not for an 39 * Open ecosystem or markets. Linux supports it *only* because Microsoft 40 * doesn't support the CDC Ethernet standard. 41 * 42 * The RNDIS data transfer model is complex, with multiple Ethernet packets 43 * per USB message, and out of band data. The control model is built around 44 * what's essentially an "RNDIS RPC" protocol. It's all wrapped in a CDC ACM 45 * (modem, not Ethernet) veneer, with those ACM descriptors being entirely 46 * useless (they're ignored). RNDIS expects to be the only function in its 47 * configuration, so it's no real help if you need composite devices; and 48 * it expects to be the first configuration too. 49 * 50 * There is a single technical advantage of RNDIS over CDC Ethernet, if you 51 * discount the fluff that its RPC can be made to deliver: it doesn't need 52 * a NOP altsetting for the data interface. That lets it work on some of the 53 * "so smart it's stupid" hardware which takes over configuration changes 54 * from the software, and adds restrictions like "no altsettings". 55 * 56 * Unfortunately MSFT's RNDIS drivers are buggy. They hang or oops, and 57 * have all sorts of contrary-to-specification oddities that can prevent 58 * them from working sanely. Since bugfixes (or accurate specs, letting 59 * Linux work around those bugs) are unlikely to ever come from MSFT, you 60 * may want to avoid using RNDIS on purely operational grounds. 61 * 62 * Omissions from the RNDIS 1.0 specification include: 63 * 64 * - Power management ... references data that's scattered around lots 65 * of other documentation, which is incorrect/incomplete there too. 66 * 67 * - There are various undocumented protocol requirements, like the need 68 * to send garbage in some control-OUT messages. 69 * 70 * - MS-Windows drivers sometimes emit undocumented requests. 71 */ 72 73 struct f_rndis { 74 struct gether port; 75 u8 ctrl_id, data_id; 76 u8 ethaddr[ETH_ALEN]; 77 u32 vendorID; 78 const char *manufacturer; 79 int config; 80 81 struct usb_ep *notify; 82 struct usb_request *notify_req; 83 atomic_t notify_count; 84 }; 85 86 static inline struct f_rndis *func_to_rndis(struct usb_function *f) 87 { 88 return container_of(f, struct f_rndis, port.func); 89 } 90 91 /* peak (theoretical) bulk transfer rate in bits-per-second */ 92 static unsigned int bitrate(struct usb_gadget *g) 93 { 94 if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER) 95 return 13 * 1024 * 8 * 1000 * 8; 96 else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH) 97 return 13 * 512 * 8 * 1000 * 8; 98 else 99 return 19 * 64 * 1 * 1000 * 8; 100 } 101 102 /*-------------------------------------------------------------------------*/ 103 104 /* 105 */ 106 107 #define RNDIS_STATUS_INTERVAL_MS 32 108 #define STATUS_BYTECOUNT 8 /* 8 bytes data */ 109 110 111 /* interface descriptor: */ 112 113 static struct usb_interface_descriptor rndis_control_intf = { 114 .bLength = sizeof rndis_control_intf, 115 .bDescriptorType = USB_DT_INTERFACE, 116 117 /* .bInterfaceNumber = DYNAMIC */ 118 /* status endpoint is optional; this could be patched later */ 119 .bNumEndpoints = 1, 120 .bInterfaceClass = USB_CLASS_COMM, 121 .bInterfaceSubClass = USB_CDC_SUBCLASS_ACM, 122 .bInterfaceProtocol = USB_CDC_ACM_PROTO_VENDOR, 123 /* .iInterface = DYNAMIC */ 124 }; 125 126 static struct usb_cdc_header_desc header_desc = { 127 .bLength = sizeof header_desc, 128 .bDescriptorType = USB_DT_CS_INTERFACE, 129 .bDescriptorSubType = USB_CDC_HEADER_TYPE, 130 131 .bcdCDC = cpu_to_le16(0x0110), 132 }; 133 134 static struct usb_cdc_call_mgmt_descriptor call_mgmt_descriptor = { 135 .bLength = sizeof call_mgmt_descriptor, 136 .bDescriptorType = USB_DT_CS_INTERFACE, 137 .bDescriptorSubType = USB_CDC_CALL_MANAGEMENT_TYPE, 138 139 .bmCapabilities = 0x00, 140 .bDataInterface = 0x01, 141 }; 142 143 static struct usb_cdc_acm_descriptor rndis_acm_descriptor = { 144 .bLength = sizeof rndis_acm_descriptor, 145 .bDescriptorType = USB_DT_CS_INTERFACE, 146 .bDescriptorSubType = USB_CDC_ACM_TYPE, 147 148 .bmCapabilities = 0x00, 149 }; 150 151 static struct usb_cdc_union_desc rndis_union_desc = { 152 .bLength = sizeof(rndis_union_desc), 153 .bDescriptorType = USB_DT_CS_INTERFACE, 154 .bDescriptorSubType = USB_CDC_UNION_TYPE, 155 /* .bMasterInterface0 = DYNAMIC */ 156 /* .bSlaveInterface0 = DYNAMIC */ 157 }; 158 159 /* the data interface has two bulk endpoints */ 160 161 static struct usb_interface_descriptor rndis_data_intf = { 162 .bLength = sizeof rndis_data_intf, 163 .bDescriptorType = USB_DT_INTERFACE, 164 165 /* .bInterfaceNumber = DYNAMIC */ 166 .bNumEndpoints = 2, 167 .bInterfaceClass = USB_CLASS_CDC_DATA, 168 .bInterfaceSubClass = 0, 169 .bInterfaceProtocol = 0, 170 /* .iInterface = DYNAMIC */ 171 }; 172 173 174 static struct usb_interface_assoc_descriptor 175 rndis_iad_descriptor = { 176 .bLength = sizeof rndis_iad_descriptor, 177 .bDescriptorType = USB_DT_INTERFACE_ASSOCIATION, 178 179 .bFirstInterface = 0, /* XXX, hardcoded */ 180 .bInterfaceCount = 2, // control + data 181 .bFunctionClass = USB_CLASS_COMM, 182 .bFunctionSubClass = USB_CDC_SUBCLASS_ETHERNET, 183 .bFunctionProtocol = USB_CDC_PROTO_NONE, 184 /* .iFunction = DYNAMIC */ 185 }; 186 187 /* full speed support: */ 188 189 static struct usb_endpoint_descriptor fs_notify_desc = { 190 .bLength = USB_DT_ENDPOINT_SIZE, 191 .bDescriptorType = USB_DT_ENDPOINT, 192 193 .bEndpointAddress = USB_DIR_IN, 194 .bmAttributes = USB_ENDPOINT_XFER_INT, 195 .wMaxPacketSize = cpu_to_le16(STATUS_BYTECOUNT), 196 .bInterval = RNDIS_STATUS_INTERVAL_MS, 197 }; 198 199 static struct usb_endpoint_descriptor fs_in_desc = { 200 .bLength = USB_DT_ENDPOINT_SIZE, 201 .bDescriptorType = USB_DT_ENDPOINT, 202 203 .bEndpointAddress = USB_DIR_IN, 204 .bmAttributes = USB_ENDPOINT_XFER_BULK, 205 }; 206 207 static struct usb_endpoint_descriptor fs_out_desc = { 208 .bLength = USB_DT_ENDPOINT_SIZE, 209 .bDescriptorType = USB_DT_ENDPOINT, 210 211 .bEndpointAddress = USB_DIR_OUT, 212 .bmAttributes = USB_ENDPOINT_XFER_BULK, 213 }; 214 215 static struct usb_descriptor_header *eth_fs_function[] = { 216 (struct usb_descriptor_header *) &rndis_iad_descriptor, 217 218 /* control interface matches ACM, not Ethernet */ 219 (struct usb_descriptor_header *) &rndis_control_intf, 220 (struct usb_descriptor_header *) &header_desc, 221 (struct usb_descriptor_header *) &call_mgmt_descriptor, 222 (struct usb_descriptor_header *) &rndis_acm_descriptor, 223 (struct usb_descriptor_header *) &rndis_union_desc, 224 (struct usb_descriptor_header *) &fs_notify_desc, 225 226 /* data interface has no altsetting */ 227 (struct usb_descriptor_header *) &rndis_data_intf, 228 (struct usb_descriptor_header *) &fs_in_desc, 229 (struct usb_descriptor_header *) &fs_out_desc, 230 NULL, 231 }; 232 233 /* high speed support: */ 234 235 static struct usb_endpoint_descriptor hs_notify_desc = { 236 .bLength = USB_DT_ENDPOINT_SIZE, 237 .bDescriptorType = USB_DT_ENDPOINT, 238 239 .bEndpointAddress = USB_DIR_IN, 240 .bmAttributes = USB_ENDPOINT_XFER_INT, 241 .wMaxPacketSize = cpu_to_le16(STATUS_BYTECOUNT), 242 .bInterval = USB_MS_TO_HS_INTERVAL(RNDIS_STATUS_INTERVAL_MS) 243 }; 244 245 static struct usb_endpoint_descriptor hs_in_desc = { 246 .bLength = USB_DT_ENDPOINT_SIZE, 247 .bDescriptorType = USB_DT_ENDPOINT, 248 249 .bEndpointAddress = USB_DIR_IN, 250 .bmAttributes = USB_ENDPOINT_XFER_BULK, 251 .wMaxPacketSize = cpu_to_le16(512), 252 }; 253 254 static struct usb_endpoint_descriptor hs_out_desc = { 255 .bLength = USB_DT_ENDPOINT_SIZE, 256 .bDescriptorType = USB_DT_ENDPOINT, 257 258 .bEndpointAddress = USB_DIR_OUT, 259 .bmAttributes = USB_ENDPOINT_XFER_BULK, 260 .wMaxPacketSize = cpu_to_le16(512), 261 }; 262 263 static struct usb_descriptor_header *eth_hs_function[] = { 264 (struct usb_descriptor_header *) &rndis_iad_descriptor, 265 266 /* control interface matches ACM, not Ethernet */ 267 (struct usb_descriptor_header *) &rndis_control_intf, 268 (struct usb_descriptor_header *) &header_desc, 269 (struct usb_descriptor_header *) &call_mgmt_descriptor, 270 (struct usb_descriptor_header *) &rndis_acm_descriptor, 271 (struct usb_descriptor_header *) &rndis_union_desc, 272 (struct usb_descriptor_header *) &hs_notify_desc, 273 274 /* data interface has no altsetting */ 275 (struct usb_descriptor_header *) &rndis_data_intf, 276 (struct usb_descriptor_header *) &hs_in_desc, 277 (struct usb_descriptor_header *) &hs_out_desc, 278 NULL, 279 }; 280 281 /* super speed support: */ 282 283 static struct usb_endpoint_descriptor ss_notify_desc = { 284 .bLength = USB_DT_ENDPOINT_SIZE, 285 .bDescriptorType = USB_DT_ENDPOINT, 286 287 .bEndpointAddress = USB_DIR_IN, 288 .bmAttributes = USB_ENDPOINT_XFER_INT, 289 .wMaxPacketSize = cpu_to_le16(STATUS_BYTECOUNT), 290 .bInterval = USB_MS_TO_HS_INTERVAL(RNDIS_STATUS_INTERVAL_MS) 291 }; 292 293 static struct usb_ss_ep_comp_descriptor ss_intr_comp_desc = { 294 .bLength = sizeof ss_intr_comp_desc, 295 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, 296 297 /* the following 3 values can be tweaked if necessary */ 298 /* .bMaxBurst = 0, */ 299 /* .bmAttributes = 0, */ 300 .wBytesPerInterval = cpu_to_le16(STATUS_BYTECOUNT), 301 }; 302 303 static struct usb_endpoint_descriptor ss_in_desc = { 304 .bLength = USB_DT_ENDPOINT_SIZE, 305 .bDescriptorType = USB_DT_ENDPOINT, 306 307 .bEndpointAddress = USB_DIR_IN, 308 .bmAttributes = USB_ENDPOINT_XFER_BULK, 309 .wMaxPacketSize = cpu_to_le16(1024), 310 }; 311 312 static struct usb_endpoint_descriptor ss_out_desc = { 313 .bLength = USB_DT_ENDPOINT_SIZE, 314 .bDescriptorType = USB_DT_ENDPOINT, 315 316 .bEndpointAddress = USB_DIR_OUT, 317 .bmAttributes = USB_ENDPOINT_XFER_BULK, 318 .wMaxPacketSize = cpu_to_le16(1024), 319 }; 320 321 static struct usb_ss_ep_comp_descriptor ss_bulk_comp_desc = { 322 .bLength = sizeof ss_bulk_comp_desc, 323 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, 324 325 /* the following 2 values can be tweaked if necessary */ 326 /* .bMaxBurst = 0, */ 327 /* .bmAttributes = 0, */ 328 }; 329 330 static struct usb_descriptor_header *eth_ss_function[] = { 331 (struct usb_descriptor_header *) &rndis_iad_descriptor, 332 333 /* control interface matches ACM, not Ethernet */ 334 (struct usb_descriptor_header *) &rndis_control_intf, 335 (struct usb_descriptor_header *) &header_desc, 336 (struct usb_descriptor_header *) &call_mgmt_descriptor, 337 (struct usb_descriptor_header *) &rndis_acm_descriptor, 338 (struct usb_descriptor_header *) &rndis_union_desc, 339 (struct usb_descriptor_header *) &ss_notify_desc, 340 (struct usb_descriptor_header *) &ss_intr_comp_desc, 341 342 /* data interface has no altsetting */ 343 (struct usb_descriptor_header *) &rndis_data_intf, 344 (struct usb_descriptor_header *) &ss_in_desc, 345 (struct usb_descriptor_header *) &ss_bulk_comp_desc, 346 (struct usb_descriptor_header *) &ss_out_desc, 347 (struct usb_descriptor_header *) &ss_bulk_comp_desc, 348 NULL, 349 }; 350 351 /* string descriptors: */ 352 353 static struct usb_string rndis_string_defs[] = { 354 [0].s = "RNDIS Communications Control", 355 [1].s = "RNDIS Ethernet Data", 356 [2].s = "RNDIS", 357 { } /* end of list */ 358 }; 359 360 static struct usb_gadget_strings rndis_string_table = { 361 .language = 0x0409, /* en-us */ 362 .strings = rndis_string_defs, 363 }; 364 365 static struct usb_gadget_strings *rndis_strings[] = { 366 &rndis_string_table, 367 NULL, 368 }; 369 370 /*-------------------------------------------------------------------------*/ 371 372 static struct sk_buff *rndis_add_header(struct gether *port, 373 struct sk_buff *skb) 374 { 375 struct sk_buff *skb2; 376 377 skb2 = skb_realloc_headroom(skb, sizeof(struct rndis_packet_msg_type)); 378 if (skb2) 379 rndis_add_hdr(skb2); 380 381 dev_kfree_skb(skb); 382 return skb2; 383 } 384 385 static void rndis_response_available(void *_rndis) 386 { 387 struct f_rndis *rndis = _rndis; 388 struct usb_request *req = rndis->notify_req; 389 struct usb_composite_dev *cdev = rndis->port.func.config->cdev; 390 __le32 *data = req->buf; 391 int status; 392 393 if (atomic_inc_return(&rndis->notify_count) != 1) 394 return; 395 396 /* Send RNDIS RESPONSE_AVAILABLE notification; a 397 * USB_CDC_NOTIFY_RESPONSE_AVAILABLE "should" work too 398 * 399 * This is the only notification defined by RNDIS. 400 */ 401 data[0] = cpu_to_le32(1); 402 data[1] = cpu_to_le32(0); 403 404 status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC); 405 if (status) { 406 atomic_dec(&rndis->notify_count); 407 DBG(cdev, "notify/0 --> %d\n", status); 408 } 409 } 410 411 static void rndis_response_complete(struct usb_ep *ep, struct usb_request *req) 412 { 413 struct f_rndis *rndis = req->context; 414 struct usb_composite_dev *cdev = rndis->port.func.config->cdev; 415 int status = req->status; 416 417 /* after TX: 418 * - USB_CDC_GET_ENCAPSULATED_RESPONSE (ep0/control) 419 * - RNDIS_RESPONSE_AVAILABLE (status/irq) 420 */ 421 switch (status) { 422 case -ECONNRESET: 423 case -ESHUTDOWN: 424 /* connection gone */ 425 atomic_set(&rndis->notify_count, 0); 426 break; 427 default: 428 DBG(cdev, "RNDIS %s response error %d, %d/%d\n", 429 ep->name, status, 430 req->actual, req->length); 431 /* FALLTHROUGH */ 432 case 0: 433 if (ep != rndis->notify) 434 break; 435 436 /* handle multiple pending RNDIS_RESPONSE_AVAILABLE 437 * notifications by resending until we're done 438 */ 439 if (atomic_dec_and_test(&rndis->notify_count)) 440 break; 441 status = usb_ep_queue(rndis->notify, req, GFP_ATOMIC); 442 if (status) { 443 atomic_dec(&rndis->notify_count); 444 DBG(cdev, "notify/1 --> %d\n", status); 445 } 446 break; 447 } 448 } 449 450 static void rndis_command_complete(struct usb_ep *ep, struct usb_request *req) 451 { 452 struct f_rndis *rndis = req->context; 453 int status; 454 455 /* received RNDIS command from USB_CDC_SEND_ENCAPSULATED_COMMAND */ 456 // spin_lock(&dev->lock); 457 status = rndis_msg_parser(rndis->config, (u8 *) req->buf); 458 if (status < 0) 459 pr_err("RNDIS command error %d, %d/%d\n", 460 status, req->actual, req->length); 461 // spin_unlock(&dev->lock); 462 } 463 464 static int 465 rndis_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl) 466 { 467 struct f_rndis *rndis = func_to_rndis(f); 468 struct usb_composite_dev *cdev = f->config->cdev; 469 struct usb_request *req = cdev->req; 470 int value = -EOPNOTSUPP; 471 u16 w_index = le16_to_cpu(ctrl->wIndex); 472 u16 w_value = le16_to_cpu(ctrl->wValue); 473 u16 w_length = le16_to_cpu(ctrl->wLength); 474 475 /* composite driver infrastructure handles everything except 476 * CDC class messages; interface activation uses set_alt(). 477 */ 478 switch ((ctrl->bRequestType << 8) | ctrl->bRequest) { 479 480 /* RNDIS uses the CDC command encapsulation mechanism to implement 481 * an RPC scheme, with much getting/setting of attributes by OID. 482 */ 483 case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8) 484 | USB_CDC_SEND_ENCAPSULATED_COMMAND: 485 if (w_value || w_index != rndis->ctrl_id) 486 goto invalid; 487 /* read the request; process it later */ 488 value = w_length; 489 req->complete = rndis_command_complete; 490 req->context = rndis; 491 /* later, rndis_response_available() sends a notification */ 492 break; 493 494 case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8) 495 | USB_CDC_GET_ENCAPSULATED_RESPONSE: 496 if (w_value || w_index != rndis->ctrl_id) 497 goto invalid; 498 else { 499 u8 *buf; 500 u32 n; 501 502 /* return the result */ 503 buf = rndis_get_next_response(rndis->config, &n); 504 if (buf) { 505 memcpy(req->buf, buf, n); 506 req->complete = rndis_response_complete; 507 req->context = rndis; 508 rndis_free_response(rndis->config, buf); 509 value = n; 510 } 511 /* else stalls ... spec says to avoid that */ 512 } 513 break; 514 515 default: 516 invalid: 517 VDBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n", 518 ctrl->bRequestType, ctrl->bRequest, 519 w_value, w_index, w_length); 520 } 521 522 /* respond with data transfer or status phase? */ 523 if (value >= 0) { 524 DBG(cdev, "rndis req%02x.%02x v%04x i%04x l%d\n", 525 ctrl->bRequestType, ctrl->bRequest, 526 w_value, w_index, w_length); 527 req->zero = (value < w_length); 528 req->length = value; 529 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC); 530 if (value < 0) 531 ERROR(cdev, "rndis response on err %d\n", value); 532 } 533 534 /* device either stalls (value < 0) or reports success */ 535 return value; 536 } 537 538 539 static int rndis_set_alt(struct usb_function *f, unsigned intf, unsigned alt) 540 { 541 struct f_rndis *rndis = func_to_rndis(f); 542 struct usb_composite_dev *cdev = f->config->cdev; 543 544 /* we know alt == 0 */ 545 546 if (intf == rndis->ctrl_id) { 547 if (rndis->notify->driver_data) { 548 VDBG(cdev, "reset rndis control %d\n", intf); 549 usb_ep_disable(rndis->notify); 550 } 551 if (!rndis->notify->desc) { 552 VDBG(cdev, "init rndis ctrl %d\n", intf); 553 if (config_ep_by_speed(cdev->gadget, f, rndis->notify)) 554 goto fail; 555 } 556 usb_ep_enable(rndis->notify); 557 rndis->notify->driver_data = rndis; 558 559 } else if (intf == rndis->data_id) { 560 struct net_device *net; 561 562 if (rndis->port.in_ep->driver_data) { 563 DBG(cdev, "reset rndis\n"); 564 gether_disconnect(&rndis->port); 565 } 566 567 if (!rndis->port.in_ep->desc || !rndis->port.out_ep->desc) { 568 DBG(cdev, "init rndis\n"); 569 if (config_ep_by_speed(cdev->gadget, f, 570 rndis->port.in_ep) || 571 config_ep_by_speed(cdev->gadget, f, 572 rndis->port.out_ep)) { 573 rndis->port.in_ep->desc = NULL; 574 rndis->port.out_ep->desc = NULL; 575 goto fail; 576 } 577 } 578 579 /* Avoid ZLPs; they can be troublesome. */ 580 rndis->port.is_zlp_ok = false; 581 582 /* RNDIS should be in the "RNDIS uninitialized" state, 583 * either never activated or after rndis_uninit(). 584 * 585 * We don't want data to flow here until a nonzero packet 586 * filter is set, at which point it enters "RNDIS data 587 * initialized" state ... but we do want the endpoints 588 * to be activated. It's a strange little state. 589 * 590 * REVISIT the RNDIS gadget code has done this wrong for a 591 * very long time. We need another call to the link layer 592 * code -- gether_updown(...bool) maybe -- to do it right. 593 */ 594 rndis->port.cdc_filter = 0; 595 596 DBG(cdev, "RNDIS RX/TX early activation ... \n"); 597 net = gether_connect(&rndis->port); 598 if (IS_ERR(net)) 599 return PTR_ERR(net); 600 601 rndis_set_param_dev(rndis->config, net, 602 &rndis->port.cdc_filter); 603 } else 604 goto fail; 605 606 return 0; 607 fail: 608 return -EINVAL; 609 } 610 611 static void rndis_disable(struct usb_function *f) 612 { 613 struct f_rndis *rndis = func_to_rndis(f); 614 struct usb_composite_dev *cdev = f->config->cdev; 615 616 if (!rndis->notify->driver_data) 617 return; 618 619 DBG(cdev, "rndis deactivated\n"); 620 621 rndis_uninit(rndis->config); 622 gether_disconnect(&rndis->port); 623 624 usb_ep_disable(rndis->notify); 625 rndis->notify->driver_data = NULL; 626 } 627 628 /*-------------------------------------------------------------------------*/ 629 630 /* 631 * This isn't quite the same mechanism as CDC Ethernet, since the 632 * notification scheme passes less data, but the same set of link 633 * states must be tested. A key difference is that altsettings are 634 * not used to tell whether the link should send packets or not. 635 */ 636 637 static void rndis_open(struct gether *geth) 638 { 639 struct f_rndis *rndis = func_to_rndis(&geth->func); 640 struct usb_composite_dev *cdev = geth->func.config->cdev; 641 642 DBG(cdev, "%s\n", __func__); 643 644 rndis_set_param_medium(rndis->config, RNDIS_MEDIUM_802_3, 645 bitrate(cdev->gadget) / 100); 646 rndis_signal_connect(rndis->config); 647 } 648 649 static void rndis_close(struct gether *geth) 650 { 651 struct f_rndis *rndis = func_to_rndis(&geth->func); 652 653 DBG(geth->func.config->cdev, "%s\n", __func__); 654 655 rndis_set_param_medium(rndis->config, RNDIS_MEDIUM_802_3, 0); 656 rndis_signal_disconnect(rndis->config); 657 } 658 659 /*-------------------------------------------------------------------------*/ 660 661 /* Some controllers can't support RNDIS ... */ 662 static inline bool can_support_rndis(struct usb_configuration *c) 663 { 664 /* everything else is *presumably* fine */ 665 return true; 666 } 667 668 /* ethernet function driver setup/binding */ 669 670 static int 671 rndis_bind(struct usb_configuration *c, struct usb_function *f) 672 { 673 struct usb_composite_dev *cdev = c->cdev; 674 struct f_rndis *rndis = func_to_rndis(f); 675 struct usb_string *us; 676 int status; 677 struct usb_ep *ep; 678 679 struct f_rndis_opts *rndis_opts; 680 681 if (!can_support_rndis(c)) 682 return -EINVAL; 683 684 rndis_opts = container_of(f->fi, struct f_rndis_opts, func_inst); 685 686 if (cdev->use_os_string) { 687 f->os_desc_table = kzalloc(sizeof(*f->os_desc_table), 688 GFP_KERNEL); 689 if (!f->os_desc_table) 690 return -ENOMEM; 691 f->os_desc_n = 1; 692 f->os_desc_table[0].os_desc = &rndis_opts->rndis_os_desc; 693 } 694 695 /* 696 * in drivers/usb/gadget/configfs.c:configfs_composite_bind() 697 * configurations are bound in sequence with list_for_each_entry, 698 * in each configuration its functions are bound in sequence 699 * with list_for_each_entry, so we assume no race condition 700 * with regard to rndis_opts->bound access 701 */ 702 if (!rndis_opts->bound) { 703 gether_set_gadget(rndis_opts->net, cdev->gadget); 704 status = gether_register_netdev(rndis_opts->net); 705 if (status) 706 goto fail; 707 rndis_opts->bound = true; 708 } 709 710 us = usb_gstrings_attach(cdev, rndis_strings, 711 ARRAY_SIZE(rndis_string_defs)); 712 if (IS_ERR(us)) { 713 status = PTR_ERR(us); 714 goto fail; 715 } 716 rndis_control_intf.iInterface = us[0].id; 717 rndis_data_intf.iInterface = us[1].id; 718 rndis_iad_descriptor.iFunction = us[2].id; 719 720 /* allocate instance-specific interface IDs */ 721 status = usb_interface_id(c, f); 722 if (status < 0) 723 goto fail; 724 rndis->ctrl_id = status; 725 rndis_iad_descriptor.bFirstInterface = status; 726 727 rndis_control_intf.bInterfaceNumber = status; 728 rndis_union_desc.bMasterInterface0 = status; 729 730 if (cdev->use_os_string) 731 f->os_desc_table[0].if_id = 732 rndis_iad_descriptor.bFirstInterface; 733 734 status = usb_interface_id(c, f); 735 if (status < 0) 736 goto fail; 737 rndis->data_id = status; 738 739 rndis_data_intf.bInterfaceNumber = status; 740 rndis_union_desc.bSlaveInterface0 = status; 741 742 status = -ENODEV; 743 744 /* allocate instance-specific endpoints */ 745 ep = usb_ep_autoconfig(cdev->gadget, &fs_in_desc); 746 if (!ep) 747 goto fail; 748 rndis->port.in_ep = ep; 749 ep->driver_data = cdev; /* claim */ 750 751 ep = usb_ep_autoconfig(cdev->gadget, &fs_out_desc); 752 if (!ep) 753 goto fail; 754 rndis->port.out_ep = ep; 755 ep->driver_data = cdev; /* claim */ 756 757 /* NOTE: a status/notification endpoint is, strictly speaking, 758 * optional. We don't treat it that way though! It's simpler, 759 * and some newer profiles don't treat it as optional. 760 */ 761 ep = usb_ep_autoconfig(cdev->gadget, &fs_notify_desc); 762 if (!ep) 763 goto fail; 764 rndis->notify = ep; 765 ep->driver_data = cdev; /* claim */ 766 767 status = -ENOMEM; 768 769 /* allocate notification request and buffer */ 770 rndis->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL); 771 if (!rndis->notify_req) 772 goto fail; 773 rndis->notify_req->buf = kmalloc(STATUS_BYTECOUNT, GFP_KERNEL); 774 if (!rndis->notify_req->buf) 775 goto fail; 776 rndis->notify_req->length = STATUS_BYTECOUNT; 777 rndis->notify_req->context = rndis; 778 rndis->notify_req->complete = rndis_response_complete; 779 780 /* support all relevant hardware speeds... we expect that when 781 * hardware is dual speed, all bulk-capable endpoints work at 782 * both speeds 783 */ 784 hs_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress; 785 hs_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress; 786 hs_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress; 787 788 ss_in_desc.bEndpointAddress = fs_in_desc.bEndpointAddress; 789 ss_out_desc.bEndpointAddress = fs_out_desc.bEndpointAddress; 790 ss_notify_desc.bEndpointAddress = fs_notify_desc.bEndpointAddress; 791 792 status = usb_assign_descriptors(f, eth_fs_function, eth_hs_function, 793 eth_ss_function); 794 if (status) 795 goto fail; 796 797 rndis->port.open = rndis_open; 798 rndis->port.close = rndis_close; 799 800 rndis_set_param_medium(rndis->config, RNDIS_MEDIUM_802_3, 0); 801 rndis_set_host_mac(rndis->config, rndis->ethaddr); 802 803 if (rndis->manufacturer && rndis->vendorID && 804 rndis_set_param_vendor(rndis->config, rndis->vendorID, 805 rndis->manufacturer)) 806 goto fail; 807 808 /* NOTE: all that is done without knowing or caring about 809 * the network link ... which is unavailable to this code 810 * until we're activated via set_alt(). 811 */ 812 813 DBG(cdev, "RNDIS: %s speed IN/%s OUT/%s NOTIFY/%s\n", 814 gadget_is_superspeed(c->cdev->gadget) ? "super" : 815 gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full", 816 rndis->port.in_ep->name, rndis->port.out_ep->name, 817 rndis->notify->name); 818 return 0; 819 820 fail: 821 kfree(f->os_desc_table); 822 f->os_desc_n = 0; 823 usb_free_all_descriptors(f); 824 825 if (rndis->notify_req) { 826 kfree(rndis->notify_req->buf); 827 usb_ep_free_request(rndis->notify, rndis->notify_req); 828 } 829 830 /* we might as well release our claims on endpoints */ 831 if (rndis->notify) 832 rndis->notify->driver_data = NULL; 833 if (rndis->port.out_ep) 834 rndis->port.out_ep->driver_data = NULL; 835 if (rndis->port.in_ep) 836 rndis->port.in_ep->driver_data = NULL; 837 838 ERROR(cdev, "%s: can't bind, err %d\n", f->name, status); 839 840 return status; 841 } 842 843 void rndis_borrow_net(struct usb_function_instance *f, struct net_device *net) 844 { 845 struct f_rndis_opts *opts; 846 847 opts = container_of(f, struct f_rndis_opts, func_inst); 848 if (opts->bound) 849 gether_cleanup(netdev_priv(opts->net)); 850 else 851 free_netdev(opts->net); 852 opts->borrowed_net = opts->bound = true; 853 opts->net = net; 854 } 855 EXPORT_SYMBOL_GPL(rndis_borrow_net); 856 857 static inline struct f_rndis_opts *to_f_rndis_opts(struct config_item *item) 858 { 859 return container_of(to_config_group(item), struct f_rndis_opts, 860 func_inst.group); 861 } 862 863 /* f_rndis_item_ops */ 864 USB_ETHERNET_CONFIGFS_ITEM(rndis); 865 866 /* f_rndis_opts_dev_addr */ 867 USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(rndis); 868 869 /* f_rndis_opts_host_addr */ 870 USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(rndis); 871 872 /* f_rndis_opts_qmult */ 873 USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(rndis); 874 875 /* f_rndis_opts_ifname */ 876 USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(rndis); 877 878 static struct configfs_attribute *rndis_attrs[] = { 879 &f_rndis_opts_dev_addr.attr, 880 &f_rndis_opts_host_addr.attr, 881 &f_rndis_opts_qmult.attr, 882 &f_rndis_opts_ifname.attr, 883 NULL, 884 }; 885 886 static struct config_item_type rndis_func_type = { 887 .ct_item_ops = &rndis_item_ops, 888 .ct_attrs = rndis_attrs, 889 .ct_owner = THIS_MODULE, 890 }; 891 892 static void rndis_free_inst(struct usb_function_instance *f) 893 { 894 struct f_rndis_opts *opts; 895 896 opts = container_of(f, struct f_rndis_opts, func_inst); 897 if (!opts->borrowed_net) { 898 if (opts->bound) 899 gether_cleanup(netdev_priv(opts->net)); 900 else 901 free_netdev(opts->net); 902 } 903 904 kfree(opts->rndis_os_desc.group.default_groups); /* single VLA chunk */ 905 kfree(opts); 906 } 907 908 static struct usb_function_instance *rndis_alloc_inst(void) 909 { 910 struct f_rndis_opts *opts; 911 struct usb_os_desc *descs[1]; 912 char *names[1]; 913 914 opts = kzalloc(sizeof(*opts), GFP_KERNEL); 915 if (!opts) 916 return ERR_PTR(-ENOMEM); 917 opts->rndis_os_desc.ext_compat_id = opts->rndis_ext_compat_id; 918 919 mutex_init(&opts->lock); 920 opts->func_inst.free_func_inst = rndis_free_inst; 921 opts->net = gether_setup_default(); 922 if (IS_ERR(opts->net)) { 923 struct net_device *net = opts->net; 924 kfree(opts); 925 return ERR_CAST(net); 926 } 927 INIT_LIST_HEAD(&opts->rndis_os_desc.ext_prop); 928 929 descs[0] = &opts->rndis_os_desc; 930 names[0] = "rndis"; 931 usb_os_desc_prepare_interf_dir(&opts->func_inst.group, 1, descs, 932 names, THIS_MODULE); 933 config_group_init_type_name(&opts->func_inst.group, "", 934 &rndis_func_type); 935 936 return &opts->func_inst; 937 } 938 939 static void rndis_free(struct usb_function *f) 940 { 941 struct f_rndis *rndis; 942 struct f_rndis_opts *opts; 943 944 rndis = func_to_rndis(f); 945 rndis_deregister(rndis->config); 946 opts = container_of(f->fi, struct f_rndis_opts, func_inst); 947 kfree(rndis); 948 mutex_lock(&opts->lock); 949 opts->refcnt--; 950 mutex_unlock(&opts->lock); 951 } 952 953 static void rndis_unbind(struct usb_configuration *c, struct usb_function *f) 954 { 955 struct f_rndis *rndis = func_to_rndis(f); 956 957 kfree(f->os_desc_table); 958 f->os_desc_n = 0; 959 usb_free_all_descriptors(f); 960 961 kfree(rndis->notify_req->buf); 962 usb_ep_free_request(rndis->notify, rndis->notify_req); 963 } 964 965 static struct usb_function *rndis_alloc(struct usb_function_instance *fi) 966 { 967 struct f_rndis *rndis; 968 struct f_rndis_opts *opts; 969 int status; 970 971 /* allocate and initialize one new instance */ 972 rndis = kzalloc(sizeof(*rndis), GFP_KERNEL); 973 if (!rndis) 974 return ERR_PTR(-ENOMEM); 975 976 opts = container_of(fi, struct f_rndis_opts, func_inst); 977 mutex_lock(&opts->lock); 978 opts->refcnt++; 979 980 gether_get_host_addr_u8(opts->net, rndis->ethaddr); 981 rndis->vendorID = opts->vendor_id; 982 rndis->manufacturer = opts->manufacturer; 983 984 rndis->port.ioport = netdev_priv(opts->net); 985 mutex_unlock(&opts->lock); 986 /* RNDIS activates when the host changes this filter */ 987 rndis->port.cdc_filter = 0; 988 989 /* RNDIS has special (and complex) framing */ 990 rndis->port.header_len = sizeof(struct rndis_packet_msg_type); 991 rndis->port.wrap = rndis_add_header; 992 rndis->port.unwrap = rndis_rm_hdr; 993 994 rndis->port.func.name = "rndis"; 995 /* descriptors are per-instance copies */ 996 rndis->port.func.bind = rndis_bind; 997 rndis->port.func.unbind = rndis_unbind; 998 rndis->port.func.set_alt = rndis_set_alt; 999 rndis->port.func.setup = rndis_setup; 1000 rndis->port.func.disable = rndis_disable; 1001 rndis->port.func.free_func = rndis_free; 1002 1003 status = rndis_register(rndis_response_available, rndis); 1004 if (status < 0) { 1005 kfree(rndis); 1006 return ERR_PTR(status); 1007 } 1008 rndis->config = status; 1009 1010 return &rndis->port.func; 1011 } 1012 1013 DECLARE_USB_FUNCTION(rndis, rndis_alloc_inst, rndis_alloc); 1014 1015 static int __init rndis_mod_init(void) 1016 { 1017 int ret; 1018 1019 ret = rndis_init(); 1020 if (ret) 1021 return ret; 1022 1023 return usb_function_register(&rndisusb_func); 1024 } 1025 module_init(rndis_mod_init); 1026 1027 static void __exit rndis_mod_exit(void) 1028 { 1029 usb_function_unregister(&rndisusb_func); 1030 rndis_exit(); 1031 } 1032 module_exit(rndis_mod_exit); 1033 1034 MODULE_LICENSE("GPL"); 1035 MODULE_AUTHOR("David Brownell"); 1036